Like peanuts, avocados contain metabolism-enhancing monounsaturated fats that have been shown to reduce hunger. In fact, a study in Nutrition Journal found that participants who ate half a fresh avocado with lunch reported a 40 percent decreased desire to eat for hours afterwards. What’s more? The trendy toast topping is also loaded with unsaturated fats, which seem to prevent the storage of belly fat, as well as satiating fiber and free-radical-killing antioxidants.
^ Sacks, Frank M.; Lichtenstein, Alice H.; Wu, Jason H.Y.; Appel, Lawrence J.; Creager, Mark A.; Kris-Etherton, Penny M.; Miller, Michael; Rimm, Eric B.; Rudel, Lawrence L.; Robinson, Jennifer G.; Stone, Neil J.; Van Horn, Linda V. (15 June 2017). "Dietary Fats and Cardiovascular Disease: A Presidential Advisory From the American Heart Association" (PDF). Circulation. 136 (3): e1–e23. doi:10.1161/CIR.0000000000000510. PMID 28620111.
OK, a bit of buzzkill news here: That rumor that chili peppers will crank up your metabolism as some kind of "fat-burning food" is a myth. Sure, they might have a modest effect on your metabolism, but nothing to produce any major effects. So, why should you still include chili peppers in your diet? Because getting creative with spices can help you lay off salt, plus, flavorful meals are always more satisfying.
A study in the journal Metabolism found that eating half a grapefruit before meals may help reduce visceral fat and lower cholesterol levels. Participants in the 6-week study who ate a Rio Red grapefruit fifteen minutes before each meal saw their waists shrink by up to an inch, and LDL levels drop by 18 points. Though researchers don’t exactly know what makes grapefruit so good at burning fat, they attribute the effects to a combination of phytochemicals and vitamin C found in the tart treat.